Christ in the midst of Israel leading and awakening Jehovah's
praises

Psalm 145 goes on in thought into the millennium, after the
distress is over, and the full deliverance can be celebrated. It is
Christ in spirit perhaps even in person as in the midst of Israel,
leading the praises of Jehovah, and awakening them amongst
men. Hence, though only expressing purpose, it is a dialogue in its
character. First, he expresses his own purpose of praising Jehovah,
and for ever and ever. One generation should do it to another. "I
will speak." One sees his heart is full of praise, and he speaks of
it (v. 5). "And men shall speak of the might of Jehovah's terrible
acts. And I will declare thy greatness. They shall speak of the
memory of thy great goodness, and shall sing of thy righteousness."
Then he breaks off most beautifully to speak of the goodness: for
still out of the abundance of the heart the mouth speaks. All
Jehovah's works shall praise Him. The saints bless Him. Their
subject shall be the glory of Jehovah's kingdom and His power, to
make known to the mass of mankind His acts, and the glorious majesty
of His kingdom, and that an everlasting one. Then in verses 14-20
His character is spoken of. Verse 21 returns to the purpose of heart
of the leader of praise. It is as man Christ speaks here "my God."
Jehovah is looked at as King. In general, the outward acts and
greatness are more in the mouth of the rest what Jehovah is in the
leader's, though he does celebrate His wondrous works. Still the
greatness and excellency and majesty of Jehovah are that which we
see his heart full of, as verses 3, 5, 8-10; and so, in general, His
gracious ways and character (v. 14-19). It is to be remarked that
there is the leader who speaks in the psalm, the saints (the Jewish
remnant), and the world in general, the sons of Adam. It is of the
highest interest in this way; because we have Messiah fulfilling the
word, "My praise shall be of thee in the great congregation." And
how full in heart He is of His praises! Jehovah's kingdom is set up;
the Messiah in the midst of Israel first, then the preserved saints,
and then, through their leading, all the world join in His praises,
for His greatness, goodness, and wonderful works.